Hydraulic Machinery for Pumped Storage Hydroelectric Power Plants: Role of Research.

The pumping hydroelectric units may be ternary or binary: the former are equipped with two hydraulic machines, one for generation and the other for pumping; the latter are equipped with only one hydraulic machine which performs the two functions by changing its rotation direction from turbine to pump operation and vice versa. The fusion of the two classical machines in a single one has been achieved thanks to the laboratory research which has allowed on the one hand to define the layouts capable of ensuring the maximum efficiency, and on the other hand to acquire a deeper knowledge of the phenomena which occur in the machine during the transients.